It was a quiet Thursday afternoon when every phone in Hugo, Colorado rang with the same message. Don't bathe, it said. Don't cook. Don't drink the water. Earlier that day—July 21—the small town's public works had detected THC in the water supply. Weed is legal in Colorado, but Hugo doesn't allow anyone to grow or sell the stuff. Was this runoff from some illegal grow operation? Science says not likely. More on that later. But THC doesn't work alone - marijuana also contains cannabidiol, a compound associated with calm and relaxation.
The ratio of THC to cannabidiol seems to be the key variable: Skunk-type strains, for instance, contain a higher ratio of THC to cannabidiol than, say, marijuana byproducts like hashish. According to a paper in Neuropsychopharmacology , "DeltaTHC and CBD can have opposite effects on regional brain function, which may underlie their different symptomatic and behavioral effects, and CBD's ability to block the psychotogenic effects of deltaTHC. Now for the bad news: These popular skunk-strains high in THC, low in cannabidiol seem to be uniquely associated with memory loss.
That, at least, is the lesson of a recent paper in the British Journal of Psychiatry. Here's Nature News :. Curran and her colleagues traveled to the homes of volunteers, where the subjects got high on their own supply before completing a battery of psychological tests designed to measure anxiety, memory recall and other factors such as verbal fluency when both sober and stoned. The researchers then took a portion of the stash back to their laboratory to test how much THC and cannabidiol it contained.
The subjects were divided into groups of high samples containing more than 0. Analysis showed that participants who had smoked cannabis low in cannabidiol were significantly worse at recalling text than they were when not intoxicated. Those who smoked cannabis high in cannabidiol showed no such impairment.
The results suggest that cannabidiol can mitigate THC's interference with memory formation. This is the first study in human to show such effects. One previous study, led by Aaron Ilan, a cognitive neuroscientist at the San Francisco Brain Research Institute in California, failed to find variations in cognitive effects with varying concentrations of cannabidiol. When you smoke cannabis, the THC at first skips the liver and goes straight to your bloodstream. Mode of ingestion, then, is a big consideration in the cannabis experience.
But so too are factors beyond your control. THC also interacts with other cannabinoids in your system, and it has a complicated relationship with CBD in particular. Anecdotally, cannabis users have reported that CBD can modulate the psychoactive effects of THC—think of it sort of like an antidote to the paranoia and anxiety that comes with being too high.
With cannabis growing more legitimate as a medicine, researchers are finally putting hard data to these anecdotal reports.
Consider the drug Marinol, a synthetic form of THC available since the s. But he was by no means seizure-free. Jacobson and Nussenbaum knew many other families struggling with epilepsy.
Many parents lacked the resources and connections they had. Everyone should have access to the drug that had so helped Sam, they thought. But that meant the F. For that to happen, real trials had to take place. And given the fraught political history of cannabis in the United States and the skepticism they would most likely face, Jacobson knew she would need top epilepsy experts to conduct those trials.
The D. Much of the research into its therapeutic potential comes from other countries, including Brazil. Later studies by Zuardi and his colleagues showed that a large dose of CBD, when given to volunteers who feared public speaking — that is, who suffer from social anxiety — blunted the flight-or-fight response, measured by increases in heart rate, blood pressure and skin conductivity, prompted by having to address others.
These were small studies, and the amount of CBD involved, which was milligrams in the social-phobia study, is greater than what users might consume these days in some CBD gummies, for example, but relieving anxiety is nonetheless one of the most widely reported reasons people use CBD.
CBD may also have antipsychotic properties. In susceptible individuals, its sister cannabinoid THC can, in high doses, induce psychotic symptoms, and heavy marijuana use early in life has been linked to an increased risk of developing psychotic disorders, possibly because it alters brain development. The scientists are now testing CBD as a prophylactic to prevent schizophrenia from even emerging.
A single milligram dose of CBD given to these patients, scientists at Kings College London have found , can partially normalize regions of the brain that have been shown in fMRI visualizations to become dysfunctional during schizophrenic episodes. A follow-up study will prophylactically treat a large group of these patients thought to be teetering on the edge of psychosis. Current schizophrenia treatments merely attempt to manage the disorder once it has already emerged.
A medicine that slows or prevents the disease from taking root altogether, almost like a vaccine, would address a huge unmet need. And precisely because the proportions between the two cannabinoids have become so skewed — the ratio of THC to CBD has risen to 80 to 1 from 14 to 1 in two decades — lots of modern cannabis is potentially much more toxic for the brain, says Hurd, who is the director of the Addiction Institute at Mount Sinai.
Now she studies how CBD could help opioid addicts kick the habit. THC may also have therapeutic uses, particularly in treating the pain that often puts people on a path leading toward opioid addiction. And opioid-related deaths have declined in states that legalized medical cannabis , suggesting that people who have access to less-addictive options for pain management may not be as likely to become hooked on opioids. Other possible applications of plant-derived cannabinoids could be just as groundbreaking.
Israeli scientists have found that CBD can lessen the incidence of graft-versus-host disease in bone-marrow transplant patients , presumably because the cannabinoid calms the immune system and deters it from attacking the patient.
How could one family of molecules help so many maladies? The most obvious response is that they might not; all this research is preliminary and might not pan out. But scientists often propose a counter-explanation: Many chronic disorders, even though they seem distinct, are characterized by dysfunction in the same few pathways. Inflammation and oxidative stress, for example, occur in schizophrenia, metabolic disorders, heart disease and other ailments. The therapeutic magic of CBD and, in some cases, THC — and maybe some of the more than other cannabinoids in cannabis — may come from the ways that, by tweaking the endocannabinoid system, they push the body away from disease toward the unruffled state scientists call homeostasis.
There are other examples of a single drug being able to help meliorate a variety of conditions. We know aspirin as a treatment for fever and headache, for example, but in low doses it is also used to reduce the risks of stroke, heart attack and pre-eclampsia in pregnant mothers; it even figures as an adjunct treatment for schizophrenia.
Aspirin has its own downsides — an elevated risk of bleeding, for instance — but like CBD, its broad utility may be partly explained by its anti-inflammatory effects. Like CBD, aspirin is derived from a plant. The active ingredient in aspirin, salicylate, was first extracted from willow bark and was a folk remedy for thousands of years before scientists finally made a pill from it in the late 19th century.
In early , just a few weeks after Sam Vogelstein returned from Britain, Catherine Jacobson organized a brainstorming session at N. The neurologists who ran the trials included Orrin Devinsky from N. In June , just five years after that meeting — an instant in drug-development time — the F. And three months later the D. The drug, called Epidiolex, is not the first cannabis-related drug on the market. Marinol, used to suppress nausea and stimulate appetite, contains THC. But Epidiolex is the first drug that contains only CBD and the first one derived directly from the cannabis plant itself.
The THC in Marinol is synthetic. Epidiolex is also noteworthy for its unusual history. Drugs are typically developed in the lab and go through trials before reaching patients.
But in the case of Epidiolex, two mothers of epileptic children experimented on their own sons and then helped push a version of what they discovered into the F.
Because so many people already use cannabis and think it helps, patients might be, in effect, pioneering new uses through self-experimentation. Users, meanwhile, look to the published literature as Jacobson did for guidance on how to use cannabinoids. The end result is that cannabis science and vernacular cannabis use exist in an uneasy symbiosis. CBD is generally considered safe, even at the high doses tested so far — and the quantities in chocolates, teas and other edibles tend to be far below the concentrations tested experimentally.
Still, many who have direct experience with CBD, including a few scientists, do not think it should be available only by prescription. They point out that long before the Controlled Substances Act, which made marijuana illegal, people used the plant medicinally. Cannabis should not only take its place as an F. It should also reclaim its role as a folk remedy. If there is a Patient Zero in the vernacular cannabis movement, that person is a girl in Colorado named Charlotte Figi.
Doctors diagnosed Dravet syndrome, in her case caused by a spontaneous genetic mutation. By the time she was 5, she was wheelchair-bound, receiving sustenance through a feeding tube, seizing about times per week, and on several occasions she had to be shocked back to life after her heart stopped. Doctors once recommended a medically induced coma just so her body could rest. Medical cannabis has been legal in Colorado since The seizures almost entirely disappeared.
Word of this success spread through the network of medical-marijuana professionals, and early in , someone called on behalf of the CNN medical correspondent Sanjay Gupta. Gupta, who is a neurosurgeon, had previously argued against the legalization of medical cannabis, but he now wanted to do a show on it.
After much discussion, Paige Figi and Joel Stanley, the Boulder-based cannabis grower who had produced the extract for Charlotte, decided to invite Gupta to tell their story. If it came from a skeptic of his standing, people might actually believe it. Gupta visited the Figi home, watched old videos of Charlotte seizing, looked at family photos, and saw the Charlotte before him as a playful little girl of 6.
At one point, Paige Figi told me, Gupta, who has daughters of his own, requested that the cameras be turned off, and cried. Figi fed them. Some stayed a few nights. One family ended up living with them for a year.
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